1. Field of the Invention
The invention relates generally to devices for toasting food items such as sandwich buns and the like and, more particularly, to an improved contact toaster that efficiently toasts a bun's interior surface, heats the bun's exterior surface and warms the bun internally.
2. Description of Related Art
Toasted sandwich buns and bread slices, when used in making hamburgers and other sandwiches, are highly valued by consumers for many reasons. For example, toasting a bun results in a carmelizing effect on its interior surfaces that provides a pleasing appearance and taste. This carmelizing effect also effectively seals the interior surfaces thereby preventing the absorption of juices from the meat and other ingredients, such as ketchup and mustard, into the bun. Accordingly, with the advent of fast-food restaurants that serve sandwiches, devices that efficiently toast a large number of buns in a short period of time have become desirable.
In response to this demand, devices such as those disclosed in U.S. Pat. Nos. 4,261,257 to Henderson et al. and 4,530,276 to Miller have been developed. These toasting devices both feature a housing containing a platen having two opposed heating surfaces. Conveyor belts are positioned on opposite sides of the platen and are spaced therefrom. The two halves of a bun are inserted into inlets at the top of the housing so that they are received into the spaces between the platen and a respective conveyor belt. The conveyor belts in turn slide the internal surfaces of the bun halves across the platen so that they are toasted. When the bun halves reach the bottom of the conveyor belts, they are disposed upon a tray at the outlet of the housing.
While devices such as those disclosed in Henderson et al. and Miller have proven to be effective in the restaurant industry, they primarily provide toasting only of the interior surfaces of the bun halves. This is a disadvantage in that, for many reasons, it is desirable to toast the exterior surfaces (i.e.: the top and bottom) of a bun as well as heat the bun body internally. Heating the bun exterior surfaces and body provides a softer and warmer overall quality to buns that consumers find pleasing. Heating the entire bun, as opposed to just the interior surfaces, also maintains the warmth of the sandwich contents for a longer period of time.
In addition, if the food item toasted is something other than typical bun halves, toasting only one side may not be sufficient. For example, many restaurants serve double or triple-decker sandwiches that feature a bun middle section with two interior surfaces or faces. It would be clearly preferable to toast both of these faces. The same can be said for situations where, instead of typical bun halves, the food items being toasted are bread slices. Accordingly, a device that heats both sides and the body of food items would have greater effectiveness and versatility.
As a result, devices such as the one disclosed in U.S. Pat. No. 5,673,610 to Stuck have been developed. The device of Stuck includes the same features as the two patents discussed above but adds a pair of resistance-type auxiliary heaters that are positioned in proximity to the conveyor belts. While this addition allows both sides of a bun half or similar food item to be heated, the device still suffers from a number of limitations.
The auxiliary heaters of Stuck toast the exterior surfaces of a pair of bun halves by radiating heat through the wire conveyor belts. This occurs as the bun halves are slid along the centrally positioned platen. Accordingly, the interior surface of each bun half is heated by contact with the platen while the exterior surface of each bun half is heated by radiated heat from the auxiliary heaters. Any heating of the bodies of the bun halves, however, occurs only by conduction of the heat from the surfaces. As a result, the heating of the bodies of the bun halves is much less than optimal.
In addition, the arrangement of Stuck limits the temperature level of the auxiliary heaters. More specifically, if the temperature of the auxiliary heaters is set too high, the wire conveyor belts will heat up and bum the exterior surfaces of the bun halves. This results in burnt belt marks on the exterior surfaces of the buns which consumers find undesirable. In addition, in extreme cases, the burnt belt marks may extend deep within the bun halves, rendering them unusable.
Limiting the temperature of the auxiliary heaters limits the speed at which the device may be operated. This is a critical consideration in the fast-food industry. If the temperature of the auxiliary heaters could be increased without burning belt marks into the buns, the device could toast many more buns in a shorter period of time.